USED, salvaged from school surplus equipment, no spec sheet, all measurements approximate.Listing is for one (1) each ladder chain sprocket for 0.185" pitch chain, nylon, single strand, held in place with roll pin (not included), comes exactly as shown in the photo.TEETH: 11BORE (Hole Size): 5/16"SET SCREW: n/aKEYWAY: n/aHUB (OD): 1/2"LTB (Length Through...